This invention relates generally to a method and apparatus for insulating ducts for use in heating, ventilating, and air conditioning applications. More particularly, this invention pertains to an insulating process and apparatus involving duct insulation having condensate wicking.
Generally, heating, ventilating, and air conditioning (HVAC) systems include such equipment as air handling units and air ducts. Typically, HVAC systems are provided with duct insulation for thermal and/or acoustic purposes. Conventional duct insulation used in HVAC systems typically includes a facing layer adhered to an insulation layer. The duct insulation is installed with the facing layer of the duct insulation positioned away from the air duct. Occasionally, water vapor may condense on the air duct. The facing layer is typically non-porous such that the facing surface acts as a barrier between the insulation body and the external environment. As such, the duct insulation is not conducive to the escape or dissipation of the condensed water vapor on or within the insulation layer. Even when the duct insulation is unfaced the condensed water vapor may remain on the duct surface or trapped in the insulation layer. As a result, damage may be caused by the condensed water vapor to the air duct, the insulation layer, or the facing layer.
According to this invention there is provided an insulated duct assembly having an elongated duct, and an insulation blanket having a inner wicking layer, the insulation blanket being applied to the elongated duct so as to form a seam aligned longitudinally with respect to the duct, the seam being defined by first and second edges of the insulation blanket. At least one sheet of escape wick material is disposed along the first edge of the insulation blanket. The first escape wick material has a xe2x80x9cCxe2x80x9d shaped cross-section surrounding the first edge of the insulation blanket. A tape layer is disposed along and covering the seam.
According to this invention there is also provided, in combination, an elongated duct, an insulation blanket, and an elongated sheet of escape wick material. The sheet of escape wick material has first and second edges and a surface, with the surface having at the first edge a strip of adhesive material, and with the surface having at the second edge a strip of adhesive material.
According to this invention there is also provided a method of forming an insulated duct assembly including wrapping an elongated duct with an insulation blanket, with the insulation blanket having an inner wicking layer. The inner wicking layer is at least partially in contact with the elongated duct, and the insulation blanket is applied to the elongated duct so as to form a seam aligned longitudinally with respect to the duct, the seam being defined by first and second edges of the insulation blanket. At least one sheet of escape wick material is adhered to the inner wicking layer at the first edge of the insulation blanket. The at least one sheet of escape wick material is adhered to an outer surface of the insulation blanket at the first edge, ands then disposed along the first edge of the insulation blanket. A tape layer is adhered to the outer surface of the insulation blanket near the first edge of the insulation blanket, and the tape layer is adhered to the outer surface of the insulation blanket near the second edge of the insulation blanket, the tape layer being disposed along the seam.
According to this invention there is also provided a sheet of escape wick material having first and second surfaces and first and second edges. A first adhesive strip is applied to the first surface at the first edge and a second adhesive strip is applied to the first surface at the second edge. The sheet of escape wick material is moldable to be formed around edges of an insulation blanket.
Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.